1. Field of the Invention
This invention relates to a method of and apparatus for making cigarettes in which shredded tobacco leaves at an end of cigarettes are stabilized to prevent them from dropping from the cigarette.
2. Description of the Prior Art
Transportation of cigarette in speed-up of in cigarette making machines considerably affects a problem in the quality of cigarettes which have an incomplete end in that the shredded tobacco leaves tend to slide from the end of the cigarettes.
Judging from the condition that cigarettes with incomplete end are produced, vibration and impact during the transportation cause shredded tobacco leaves to slide from an inner surface of the paper wrapper, then, the shredded tobacco leaves drop one after another due to a lock of adhesion between the shredded tobacco leaves resulting in production of cigarettes with an incomplete end. The sliding of the shredded tobacco leaves from the inner surface of the paper wrapper is more susceptible than the dropping of the leaves from a center of the end.
Therefore, it is necessary to reduce cigarettes with an incomplete end in the cigarette making process to thereby improve quality of the cigarettes.
As a method for preventing production of the cigarettes with incomplete end, more shredded tobacco leaves are put at a portion adjacent to a cut face of the cigarette than the other portion to increase frictional force between shredded tobacco leaves. As a result, the shredded tobacco leaves are prevented from sliding from the end.
That is, as shown in FIG. 9, shredded tobacco leaves pneumatically transported in a feed passage 1 are absorbed on a lower surface of a suction conveyor 2 and the shredded tobacco leaves T are fed to a trimming disk 3.
As described in FIG. 10, the trimming disk 3 is provided with two disks 3a and 3b parallel to each other with five concave portions 4 on the outer surface thereof and a feed passage is formed for the shredded tobacco leaves T between the rotating disks 3a and 3b.
Since the shredded tobacco leaves T are accommodated and transported in a heap to a paper wrapper 5 after passing through the trimming disk 3, portions 6 containing more shredded tobacco leaves than the other portion are produced. The distance 1 between the portions 6 is identical with the circumferential pitch of the concave portions 4.
As a result, when the paper wrapper 5 is wound at the succeeding process to form a cigarette, the portions 6 are packed with more shredded tobacco leaves, and frictional force is increased between the shredded tobacco leaves. Therefore, when a cigarette rod is cut at the portions 6 to produce a single cigarette having a length 1, it is difficult for the shredded tobacco leaves to slide from the end, preventing the cigarettes with incomplete end from being produced.
Although this method is effective to prevent a cigarette with an incomplete end from being produced, actually, more shredded tobacco leaves should be packed at a portion adjacent the end, resulting in loss of tobacco leaves.
Meanwhile, as other prior arts for preventing cigarettes with incomplete end from being produced, Japanese Utility Model Application Pub. Nos. 48-40500 and 60-182796 are disclosed.
Prior art disclosed in the former Japanese Utility Model Application Pub. No. 48-40500 is for preventing shredded tobacco leaves from dropping by pasting a piece of paper or the like on an end of a cigarette. On the other hand, in prior art disclosed in the latter Utility Model Application Pub. No. 60-182796, an end of a cigarette is covered by a piece of paper or a tobacco leaf, or an adhesive is sprayed, applied, or impregnated on an end of a cigarette.
However, it is not easy to cover an end of a cigarette by a lid while maintaining appearance of the cigarette. Moreover, there is a problem that a new apparatus for applying the lid must be added in the cigarette making process.